The team analyzed data of Salmonella enterica reported to the Foodborne Diseases Active Surveillance Network (FoodNet) from 1996 to 2009 and compared it with data collected from other surveillance systems.

The largest increases by demographic were in young children, older adults, and residents of southern states, researchers found. They identifed chicken and eggs as likely major sources of infection.

Although many cases go unreported, Salmonella enterica causes an estimated 1 million cases of domestically acquired foodborne illness in the U.S. each year, according to the study. The serotype, Salmonella Enteritidis (SE) is one of the most common Salmonella serotypes, according to the Centers for Disease Control and Prevention (CDC).

There have been a number of foodborne Salmonella outbreaks this year. Two of them were from domestic sources: